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Context. Mid- and far-infrared observations of the environment around embedded protostars reveal a plethora of high excitation molecular and atomic emission lines. Different mechanisms for the origin of these lines have been proposed, including shocks induced by protostellar jets and radiation or heating by the embedded protostar of its immediate surroundings. Aims. By studying of the most important molecular and atomic coolants, we aim at constraining the physical conditions around the embedded protostars SMM3 and SMM4 in the Serpens molecular cloud core and measuring the CO/H2 ratio in warm gas. Methods. Spectro-imaging observations from the Spitzer Infrared Spectrograph (IRS) and the Herschel Photodetector Array Camera and Spectrometer (PACS) provide an almost complete wavelength coverage between 5 and 200 μm. Within this range, emission from all major molecular (H2, CO, H2O and OH) and many atomic ([OI], [CII], [FeII], [SiII] and [SI]) coolants of excited gas are detected. Emission line maps reveal the morphology of the observed emission and indicate associations between the different species. The excitation conditions for molecular species are assessed through rotational diagrams. Emission lines from major coolants are compared to the results of steady-state C- and J-type shock models. Results. Line emission tends to peak at distances of ~10-20'' from the protostellar sources with all but [CII] peaking at the positions of outflow shocks seen in near-IR and sub-millimeter interferometric observations. The [CII] emission pattern suggests that it is most likely excited from energetic UV radiation originating from the nearby flat-spectrum source SMM6. Excitation analysis indicates that H2 and CO originate in gas at two distinct rotational temperatures of ~300 K and 1000 K, while the excitation temperature for H2O and OH is ~100-200 K. The morphological and physical association between CO and H2 suggests a common excitation mechanism, which allows direct comparisons between the two molecules. The CO/H2 abundance ratio varies from ~10-5 in the warmer gas up to ~10-4 in the hotter regions. Shock models indicate that C-shocks can account for the observed line intensities if a beam filling factor and a temperature stratification in the shock front are considered. C-type shocks can best explain the emission from H2O. The existence of J-shocks is suggested by the strong atomic/ionic (except for [CII]) emission and a number of line ratio diagnostics. Dissociative shocks can account for the CO and H2 emission in a single excitation temperature structure. Conclusions. The bulk of cooling from molecular and atomic lines is associated with gas excited in outflow shocks. The strong association between H2 and CO constrain their abundance ratio in warm gas. Both C- and J-type shocks can account for the observed molecular emission; however, J-shocks are strongly suggested by the atomic emission and provide simpler and more homogeneous solutions for CO and H2. The variations in the CO/H2 abundance ratio for gas at different temperatures can be interpreted by their reformation rates in dissociative J-type shocks, or the influence of both C and J shocks. [ABSTRACT FROM AUTHOR]

Objective: To determine the feasibility and efficacy of using a bone cement, Oto-Cem, to reconstruct the ossicular chain.Study Design: Prospective clinical trial on nine consecutively chosen adult patients with ossicular chain defects.Patients and Setting: Nine patients with ossicular chain defects involving the long process of the incus were treated at the Carolina Ear and Hearing Clinic. The ossicular chain was reconstructed using bone cement by itself or in conjunction with a stapes prosthesis.Main Outcome Measures: Preoperative audiograms were compared with audiograms 3, 6, and 12 months after reconstruction.Results: There was a mean pure-tone average (PTA) improvement of 15 dB in patients undergoing incus to stapes suprastructure reconstruction with the bone cement. The incus to mobile footplate reconstruction (using a stapes prosthesis attached to the newly reconstructed incus) resulted in a 34-dB PTA postoperative improvement. Two of the three patients with incus to oval window repairs experienced a 10-dB improvement in PTA. One of the three patients experienced a loss in speech discrimination and a 2-dB loss in PTA.Conclusions: Despite the limited number of patients, this preliminary study demonstrates the effectiveness of Oto-Cem in reconstructing a foreshortened incus. There was a substantial hearing improvement in all but one patient in the incus to stapes or the incus to footplate categories. [ABSTRACT FROM AUTHOR]

Tapetal Changes in Beagle Dogs following Oral Administration of CGS 14796C, A Potential Aromatase Inhibitor. SCHIAVO, D. M., GREEN, J. D., TRAINA, V. M., SPAET, R., AND ZAIDI, I. (1988) . 10, 329-334. CGS 14796C, m-l-[(4-[(l-imidazolyl)methyl]-cyclohexyl)methyl)imidazole succinate, has been evaluated as a potential aromatase inhibitor. As part of the safety evaluation program, a 3-month oral toxicity study was performed in which beagle dogs were administered CGS 14796C by gavage at 5, 15, or 50 mg/kg/day. Ophthalmos-copically, changes in the tapetum lucidum affecting dogs from the 15 and 50 mg/kg dose levels were diffuse areas of pigmentation varying in appearance from a brownish peppered or mottled to a more uniform brown similar to that of the nontapetal area of the fundus. Tapetal reflectivity was absent or markedly reduced. Within the pigmented area, multiple islets (yellow, green, or orange) of tapetal cells were visible, suggestive of destruction of the tapetum. In no instance was retinal destruction, edema, vascular changes, or detachment observed. Ophthalmoscopic examinations performed during recovery revealed changes of slight increase in tapetal islets, suggestive of a slight progression and organization within the tapetum followed by an arrest of the toxic insult within the tapetal tissue. At light and electron microscopic examination of the ocular tissues, the lesions were tapetal cell degeneration/atrophy. These results demonstrated that the taptetum lucidum was a target tissue of toxicity for CGS 14796C, and indicated that the findings are without toxicological significance in atapetal species, including man, whose globes do not have this Structure. [ABSTRACT FROM PUBLISHER]